Nonlinear scattering of laser radiation by absorbing microinhomogeneities in BK-8 glass

An experimental investigation was made of nonlinear scattering of laser radiation by absorbing microinhomogeneities in BK-8 glass. Curves giving the time evolution of the scattered radiation were obtained for the same inhomogeneous inclusion but different power densities of the incident radiation. It was observed that nonlinear scattering may be found even for power densities almost half the threshold value. Theoretical calculations showed that a model based on changes in the optical characteristics of the medium as a result of high-temperature heating of absorbing microinhomogeneities can give a good quantitative description of the experimental dependences.